The present invention relates generally to a motor, and more particularly to a fixing enhancement mechanism for large iron core.
FIG. 1 shows an iron core 1 of a conventional large-size motor for winding a winding coil thereon. In manufacturing, due to the limitation of the large size, the iron core 1 is generally divided into multiple arc-shaped blocks 1a to facilitate processing.
FIG. 2 shows a measure for assembling the arc-shaped blocks 1a into the iron core 1. The arc-shaped blocks 1a are connected and assembled into a complete ring-shaped iron core 1 with their curvature centers coinciding with each other. After assembled, the iron core 1 is fixedly enclosed in a tubular housing 2. Such measure is able to accurately and firmly fix the iron core 1. However, it is necessary to manufacture an even larger housing for accommodating the iron core 1. This leads to increment of manufacturing cost and troublesomeness in assembling process. Moreover, with the housing 2 as a component of the motor, the heat generated by the motor in operation will be hindered by the housing 2 from dissipating outward. As a result, the operation efficiency will be affected due to poor heat dissipation efficiency.
FIG. 3 shows another conventional measure for fixing the iron core 1 without resulting in heat dissipation problem. Two end rings 3 are coaxially fixedly connected to two axial ends of the iron core 1 to hold and lock arc-shaped blocks 1a together. Such fixing measure simply applies an axial force to the iron core 1 and only provides very little component force normal to the axis of the iron core 1. Therefore, it is necessary to further clamp the end rings 3 and the iron core 1 with two end boards 4. In addition, several circular rods 5 are bridged and locked between the end boards 4 to enhance the fixing force of the end rings 3 to the iron core 1. The additional end boards 4 leads to increment of manufacturing cost. Furthermore, the end boards 4 still mainly apply an axial force to the iron core 1. The circular rods 5 are spaced from the iron core 1 by a certain distance to provide a component force normal to the axis of the iron core 1. However, the magnitude of the component force is in proportion to the distance between the iron core 1 and the circular rods 5. Therefore, for achieving better iron core fixing effect, it is necessary to enlarge the distance between the circular rods 5 and the iron core 1. This will lead to excessively large volume and waste of room.